“The question that we face with the show is that the books continue to get bigger and bigger, and the show really can’t get much bigger,” he said. “We’re the most expensive television show in the world right now, and we have the biggest cast, as far as I know, of any show on television.” Martin compared the budget of a three-hour fantasy film—at around $200 million—to that of a roughly $60-million television budget for 10 episodes of “Thrones.”

“We can’t keep adding characters and making the show more and more expensive—we’re pushing up against the limits there,” said Martin. “So we’d either have to make some cuts going forward, and simplify the story, or we have to increase the format.”

George R.R. Martin in March

Amanda Schwab/Starpix

“I happen to know, someone has told me—some source that I won’t name—that there will be some major battles coming up: some dragon action, and some stuff with the Wall and White Walkers. It looks to be kind of expensive,” he added, laughing.

“How are we going to do that? I don’t know,” he said. “I’m not saying that [the movies are] going to happen, and it’s not my idea. It’s just an idea that I’ve endorsed, let us say. And I’d love to see it, but I think the odds are against it. They’re probably not going to happen.”

In the interview, Martin also talks about writing strong female characters, how journalism helped him come out of his shell, and why he’s more interested in heroism rather than heroes.

About Speakeasy

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